Set and Weakset

Questions

1. How set is different from Map
2. How set is different from Array
3. Set vs WeakSet

Set

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A set is a special type of collection in Javascript Unless an array set holds only unique values without any keys where each value occurs only once.

Salient Features of Set

Set methods

• new Set(iterable) – creates the set, and if an iterable object is provided (usually an array), copies values from it into the set.
• set.add(value) – adds a value, returns the set itself.
• set.delete(value) – removes the value, returns true if value existed at the moment of the call, otherwise false.
• set.has(value) – returns true if the value exists in the set, otherwise false.
• set.clear() – removes everything from the set.
• set.size – is the elements count.

Set Iteration Methods

• set.keys() – returns an iterable object for values,
• set.values() – same as set.keys(), for compatibility with Map,
• set.entries() – returns an iterable object for entries [value, value], exists for compatibility with Map.

WeakSet

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WeakSet behave similarly as a Set but it only allows objects as values, primitive values are not allowed. But WeakSet do not support iteration methods/properties like weakSet.keys() or Size

And WeakSet also has the nature of WeakMap which is automatic garbage collection if any value in the WeakSet don't have any references